NFC allows users to benefit from contactless payments using their credit or debit card.

At present Computerworld UK understands that it is just buses that will be going live with the technology. TfL was unwilling to disclose what proportion of the network was going live or when it would be extended to the Underground.

Further information is expected to be released on Thursday, but TfL has previously said that the project will not be completed until the end of 2013.

Shashi Verma, TfL's director of customer experience, said earlier this year: "We are leading the world in pioneering this exciting new technology that will make paying for journeys quicker, easier and more convenient for passengers on London's transport network. We will only roll it out once we are confident it is 100 percent robust.